Moodle Cross-site Scripting vulnerabilityGHSA-fm6m-fg23-67jq
MEDIUMGHSA-fm6m-fg23-67jq is a medium-severity (CVSS 5.4) Cross-site Scripting (XSS) vulnerability in moodle/moodle. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for moodle/moodle — see the affected versions and patch details below.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
moodle/moodle🐘moodle/moodle🐘moodle/moodleReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
In certain Moodle products after creating a course, it is possible to add in a arbitrary "Topic" a resource, in this case a "Database" with the type "Text" where its values "Field name" and "Field description" are vulnerable to Cross Site Scripting Stored(XSS). This affects Moodle 3.11.x prior to 3.11.10, Moodle 3.10.4, and Moodle 3.9.7.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | moodle/moodle | all versions | No fix |
| 🐘Packagist | moodle/moodle | ≥ 3.10.0 | No fix |
| 🐘Packagist | moodle/moodle | ≥ 3.11.0&&< 3.11.10 | 3.11.10composer require moodle/moodle:^3.11.10 |
Affected Products
fedorafedoraprojectmoodlemoodleResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for moodle/moodle, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
A fix is available for GHSA-fm6m-fg23-67jq; check the affected-versions list above or the advisory for the patched release of moodle/moodle, then make sure no transitive dependency still pins the vulnerable range.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.
Frequently Asked Questions
Is GHSA-fm6m-fg23-67jq in your dependencies?
Find it across Packagist, including transitive dependencies.